The monthly cohort matrix
Rows are customer acquisition month. Columns are month 0, 1, 2, 3+ revenue. Shows whether new customers are improving or degrading.
What good looks like
Later cohorts should outperform earlier ones at the same age. If they don't, your acquisition channels are becoming less efficient.
What to do if it worsens
New cohorts underperforming usually means paid channels are pulling in lower-quality customers. Creative/audience intervention needed.